RBANS embedded measures of suboptimal effort in dementia: effort scale has a lower failure rate than the effort index

The importance of evaluating effort in neuropsychological assessments has been widely acknowledged, but measuring effort in the context of dementia remains challenging due to the impact of dementia severity on effort measure scores. Two embedded measures have been developed for the repeatable battery for the assessment of neuropsychological status (RBANS; Randolph, C., Tierney, M. C., Mohr, E., & Chase, T. N. (1998). The repeatable battery for the assessment of neuropsychological status (RBANS): Preliminary clinical validity. Journal of Clinical and Experimental Neuropsychology, 20 (3), 310-319): the Effort Index (EI; Silverberg, N. D., Wertheimer, J. C., & Fichtenberg, N. L. (2007). An effort index for the repeatable battery for the assessment of neuropsychological status (RBANS). Clinical Neuropsychologist, 21 (5), 841-854) and the Effort Scale (ES; Novitski, J., Steele, S., Karantzoulis, S., & Randolph, C. (2012). The repeatable battery for the assessment of neuropsychological status effort scale. Archives of Clinical Neuropsychology, 27 (2), 190-195). We explored failure rates on these effort measures in a non-litigating mixed dementia sample (N = 145). Failure rate on the EI was high (48%) and associated with dementia severity. In contrast, failure on the ES was 14% but differed based on type of dementia. ES failure was low (4%) when dementia was due to Alzheimer disease (AD), but high (31%) for non-AD dementias. These data raise concerns about use of the RBANS embedded effort measures in dementia evaluations.